Perhaps more widely recognized than any vegetarian sub-group, "lacto-ovo vegetarians" are vegetarians whose meal plans consist of plant foods plus animal milks, cheeses, and yogurts made from animal milks, and eggs from chickens or other animals. In the name of this subgroup, "lacto" comes from the Latin word lac meaning "milk," and "ovo" from the Latin word ovum meaning "egg."
This dietary approach follows an ethical philosophy that draws a clear line between the consumption of foods produced by animals versus consumption of the animals themselves. It is possible to consume both eggs and milk without harming the animals who produced them, even though prevention of harm is by no means guaranteed unless the person who is raising, milking, and tending to the animals takes special care in doing so. Below are some stand-out features of a lacto-ovo vegetarian diet.
- Broad nutrient support: If you consider lacto-ovo foods as a group (cheese plus yogurt plus eggs plus milk), you will find a combination of foods that offers an impressive variety of nutrients. Here are some examples of nutrient "mixing and matching" from this group. From eggs, you are not going to get much calcium—less than 3% of our daily recommended amount from one egg. But from yogurt or cow's milk you can get about 30% of our recommended daily amount for calcium in one cup. Or let's take an example that works in the opposite direction. In a single egg, you can get about 25% of our daily recommended selenium. However, to get this same amount from milk or yogurt, you would need to consume about 2.5 cups. A single hen's egg can provide you with more than 15% of seven recommended nutrients, including nutrients like vitamin B12 that can be difficult to obtain on a vegetarian meal plan. If you combine all foods in this group together, you will find it to contain good, very good, or excellent amounts of 12 out of 29 nutrients that we rank on our website.
- B12 Support: All 4 of our dairy/eggs rank in the Top 15 foods for vitamin B12, which can be a difficult nutrient to obtain in rich amounts on a vegetarian meal plan. We're talking about 37% of our recommended daily B12 intake from 8 ounces of yogurt, 23% from 4 ounces of cow's milk or 1 egg, or 10% from one ounce of cheese. While not as B12-rich as beef at 60% of the recommended amount in 4 ounces, foods in the dairy/egg group still offer significant amounts of this B vitamin.
- Omega-3s, grass feeding, and pasture raising: Dairy/eggs are foods that can provide substantial amounts of omega-3s, particularly when the animals providing them have been grass-fed or pasture-raised. Natural food supplies for cows and chickens (and other animals) typically contain numerous varieties of omega-3 foods, and these omega-3s can be passed on when we consume milks or eggs from the animals.
From a nutritional standpoint, lacto-ovo vegetarian eating is an approach that makes sense to us, although we also believe that it is important to stay focused on a diverse mix of plant foods as the basis of this approach and to avoid swinging the dietary balance over to dairy/eggs as the foundation of this meal plan. There is too much potential in this group for excessive intake of certain fats—as well as overall calories—if dairy/eggs become the focus of the plan. A multiple-egg cheese omelet 3-4 times per week is not what we have in mind here, but something more like our 1-egg-per-serving Poached Eggs Over Collard Greens & Shiitake Mushrooms 1-2 days per week, or our 10-Minute Energizing Oatmeal several days per week with its 1/2-cup of milk per serving.
More Information on Vegetarian Diets
For more information on the subject of vegetarian diets, please see our overview article "A Practical Look at Vegetarian Diets" as well as the following Q+As.
To see the research articles we reviewed in the writing of these articles, see here.